Mitsubishi Hitachi Power Systems, Ltd.

Hitachi, Ltd.

Iwaya Corporation

Mitsubishi Heavy Industries Limited

Shinji Oikawa

Hiroyuki Doi

Kenichi Murata

Shinya Imano

Shunsuke Mizumi

Takeshi Kudo

Masahiko Arai

Hideo Yoda

Akira Yoshinari

Takeshi Izumi

Kiyoshi Segawa

Jun Sato

Jiro Yamaguchi

Koji Ogata

Yuta Yanase

A steam turbine rotor blade achieving both abrasion resistance and reliability, and a method for manufacturing a steam turbine rotor blade capable of obtaining such a steam turbine rotor blade are provided. A steam turbine rotor blade according to the invention is characterized by including a blade base material and an erosion shield formed on a surface of the blade base material, wherein the blade base material is composed of a titanium alloy, and the erosion shield is composed of a weld overlay layer including a parent phase composed of pure titanium in which a metal element is solid-dissolved or a titanium alloy in which a metal element is solid-dissolved, and a hard phase dispersed in the parent phase.

Steam turbine rotor blade and method for manufacturing steam turbine rotor blade

It is an objective of the invention to provide a steam turbine rotor of which a rotor shaft is made of a low-cost heat resistant ferritic steel and that can withstand high main steam temperatures of about 650&#xb0; C. There is provided a steam turbine rotor comprising: a rotor shaft made of a heat resistant ferritic steel such as a 12-Cr steel; and a rotor blade made of a Ti&#x2014;Al alloy, wherein the Ti&#x2014;Al alloy includes: from 38 to 45 atomic % of Al; from 0.5 to 2 atomic % of V; from 2 to 6 atomic % of Cr and/or Mo; and the balance being Ti and incidental impurities.

Steam turbine rotor, steam turbine including same, and thermal power plant using same

It is an objective of the present invention to provide a precipitation-hardening martensitic stainless steel having well-balanced properties of high mechanical strength, high toughness and good corrosion resistance properties. There is provided a precipitation-hardening martensitic stainless steel comprising: 0.10 mass % or less of C; 13.0 to 15.0 mass % of Cr; 7.0 to 10.0 mass % of Ni; 2.0 to 3.0 mass % of Mo; 0.5 to 2.5 mass % of Ti; 0.5 to 2.5 mass % of Al; 0.5 mass % or less of Si; 0.1 to 1.0 mass % of Mn; and the balance including Fe and incidental impurities, in which the mass % content of the Ti (represented by [Ti content]), the mass % content of the Al (represented by [Al content]) and the mass % content of the C (represented by [C content]) satisfy relationships of '0.5&#x2266;[Ti content]&#x2266;2.5' and '0.5&#x2266;[Al content]+2[C content]&#x2266;2.7'.

Precipitation hardening martensitic stainless steel and steam turbine component made thereof

The problem to be solved of the present invention is to provide a precipitation hardening martensitic stainless steel having excellent tissue stability, strength, toughness, and corrosion-resistance, requiring no sub-zero treatment, and having excellent productivity; and also a steam turbine long blade using the same. The problem is solved by providing a precipitation hardening martensitic stainless steel containing, by mass, 0.1% or less of C; 0.1% or less of N; 9.0% or more and 14.0% or less of Cr; 9.0% or more and 14.0% or less of Ni; 0.5% or more and 2.5% or less of Mo; 0.5% or less of Si; 1.0% or less of Mn; 0.25% or more and 1.75% or less of Ti; 0.25% or more and 1.75% or less of Al, and the rest is Fe and inevitable impurities; and a steam turbine long blade using the precipitation hardening martensitic stainless steel.

Precipitation hardening martensitic stainless steel, and steam turbine long blade, steam turbine, and power plant using the same

There is provided a steam turbine rotor with high reliability and corresponding to increase in length of a high strength steel blade, in which only a low-pressure last stage is highly strengthened. The steam turbine rotor includes a steam turbine low-pressure last stage long blade made of a precipitation hardening type martensitic stainless steel containing, in mass, 0.1% or less of C, 0.1% or less of N, 9.0% to 14.0% inclusive of Cr, 9.0% to 14.0% inclusive of Ni, 0.5% to 2.5% inclusive of Mo, 0.5% or less of Si, 1.0% or less of Mn, 0.25% to 1.75% inclusive of Ti, 0.25% to 1.75% inclusive of Al, and the balance consisting of Fe and inevitable impurities, and a disk having a specific alloy composition is joined to a last stage section of the turbine rotor made of a low-alloy steel.

Steam turbine rotor

As a precipitate hardening stainless steel has excellent structure stability, strength, toughness, and corrosion resistance, requires no sub-zero treating and is excellent in terms of productivity, a long blade for a steam turbine uses the same. The following are provided: a precipitate hardening stainless steel, which comprises C at 0.05 mass % or less, N at 0.05 mass % or less, Cr at 10.0 mass % to 14.0 mass %, Ni at 8.5 mass % to 11.5 mass %, Mo at 0.5 mass % to 3.0 mass %, Ti at 1.5 mass % to 2.0 mass %, Al at 0.25 mass % to 1.00 mass %, Si at 0.5 mass % or less, and Mn at 1.0 mass % or less, and the balance is composed of Fe and inevitable impurities. The long blade for a steam turbine is composed of this precipitate hardening stainless steel.

Precipitate hardening stainless steel and long blade using same for steam turbine

A precipitation hardenable martensitic stainless steel excellent in the stability of martensite, having the high strength, high toughness and high corrosion resistance is provided. The precipitation hardenable martensitic stainless steel contains at a mass rate, C: 0.05-0.10%, Cr: 12.0-13.0%, Ni: 6.0-7.0%, Mo: 1.0-2.0%, Si: 0.01-0.05%, Mn: 0.06-1.0%, Nb: 0.3-0.5%, V: 0.3-0.5%, Ti: 1.5-2.5%, Al: 1.0-2.3%, and the remainder consisting of Fe and an unavoidable impurity.

Precipitation hardenable martensitic stainless steel and steam turbine blade using the same

A motion toy body consisting of a trunk containing a housing therein, and a head; a frame in the housing which can be vertically moved, and which supports a crankshaft on which left and right feet are mounted so that the feet can be moved forward and backward; a slide shaft supported by a frame so that the slide shaft can be moved axially and turned, and which has a change-over gear, adapted to engage and disengage from a foot-driving gear by which power is transmitted to the crankshaft, and a singing gear; a screw on the outer circumferential surface of the slide shaft; a support member fixed to a bottom member of the housing and having a feed screw adapted to be engaged with and disengaged from the screw on the slide shaft and thereby move the slide shaft when the feed screw is engaged with the screw on the slide shaft; a spring fitted around the slide shaft for urging the slide shaft constantly toward the support member; an electric motor fixed to the frame and adapted to turn the slide shaft; a spring provided between the housing and the frame and resiliently supporting the frame with the screw on the slide shaft lower than the feed screw on the support member; a switch mechanism adapted to energize the electric motor when the frame is raised against the spring; and a singing member proivided on the bottom member of the housing and having a slide portion which the singing gear engages and disengages from.

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Hitachi, Japan

Shinji Oikawa